1. Technical Field
The invention relates to accessing information in computer systems. More particularly, the invention relates to a graphical user interface for computerbased systems.
2. Description of the Prior Art
In prior art computer systems, information, such as contained in a file structure, may be accessed in any of several ways. FIG. 1 is a perspective view of a computer system 10, according to the prior art, showing a keyboard 12 command used to access a computer database stored on a hard disk drive 14. Individual areas which define commands or items in a menu may be highlighted by using a pointing device, such as a mouse 18 or trackball. When selected, the highlighted area opens to display information that may be accessed in such area or commands that may be issued to the computer from such area. This information is displayed on the computer monitor 16. The display area is organized in modern computer systems to resemble a familiar workspace, and is known metaphorically as the desktop 20.
A desktop is typically configured to represent information stored in the computer, or commands available to operate various features of the computer, in a convenient manner. For example, a word processing category can include subcategories for each individual word processing program. Each program, in turn, can include subcategories for program modules, such as templates, a spell checker, and font storage. The graphical user interface embodied in the desktop effectively exploits this information structure.
Such graphical user interface, in conjunction with the desktop, provides interactive, graphical or pictorial, displays that represent organized information, commands, and/or file structures within the computer system. For example, a graphical representation in the form of an icon, pull down menu, or scroll bar may be provided for such items as a computer operating system, a word processing program, stored financial data, or communication software. Selecting a particular graphical representation provides access to its contents, such as the stored financial data; and/or provides access to additional levels of information, if the information is organized hierarchically. Selecting a graphical representation of a software program, such as a virus checker program, launches the program.
Thus, a hierarchy of graphical representations, e.g. icons, may be organized in nested layers. FIG. 2 is a front view of a computer display 20 showing pictorial icons 22 according to the prior art. Selecting the word processor icon 24 produces a display of the program module icons 26. The nested layers may be indented.
It is known to use a scrollbar 21 to access window contents that are not displayed. The scrollbar typically includes arrows 23 that are selected to move the contents display up, down, left, or right. The scrollbar may also include an interactive area 25 that spatially represents a location within the window.
Selecting a part of this interactive area causes the corresponding location of the window to be displayed.
A scrollbar is often inconvenient to use when large file structures are open for display. The user must select a directional arrow and wait for the file of interest to scroll to the appropriate window location. Alternatively, the user must guess the location on the interactive area that corresponds to that of the desired file location file.
A graphical user interface does not eliminate the need for a text-based structure. However, the use and presentation of the text commands is significantly changed from the older text-based operating systems. FIG. 3 is a front view of a computer display 20 showing a text-based menu bar 32 according to the prior art.
For example, a typical software program includes a text menu that is displayed when the program is running. This text menu is frequently organized in a hierarchical file structure. A word processor text menu may include categories for File 33, Layout 34, Font 28, and Utilities 36. The Utilities category may include a spell checker 37, word counter 38, or equation editor 39.
The textual representations in the menu include both hierarchical storage categories and commands. Selecting the command "Quit". causes a software program to shut down. Selecting the storage category "Font" 28 produces a display of the fonts 30 stored on the computer that are available to the program. A particular font may be selected by scrolling through this category. In effect, the text itself is used as a graphical representation of the underlying category or command. Instead of typing in a text-based command, the user selects a pre-existing text representation in the same manner as selecting a pictorial icon.
In one system known in the prior art, a selected icon or text opens a window, i.e. a dedicated display area on the desktop, to display a folder, i.e. a graphical representation of a category. The folder is opened to show the next tier of nested subcategories contained therewithin. It is possible to mix both icons and text within a single folder. For example, a word processor program folder may have a pictorial icon. When the icon is selected, the word processor folder opens to display a window showing a textual listing of categories. Selecting an individual text category opens a window to display icons representing the next tier of subcategories.
Any number of these windows may be kept open at the same time on the desktop. However, the desktop has a limited area. Keeping too many open windows clutter the desktop and makes it difficult to locate desired information. Furthermore, the greater the number of open windows on the desktop, the smaller the size each one must be to be fully displayed. As the size of a window decreases, the amount of its contents that can be displayed, as well as its legibility, also decreases. While an individual window can be resized, the size of the contents of that window, whether icon or text, remains the same. Thus, the smaller the window, the fewer the icons displayed. The more entries in a list, the greater the amount of entries that are not displayed in the window.
Another display known in the prior art is the "tree." Highlighting a folder or icon spatially displays its contents. The user can move through each "branch" on the display to reach lower level tiers of subcategories. The spatial representation of the file tree is advantageous in that the user always knows the location of a particular category or folder within the data structure.
The entries in each tier of the file tree may be displayed in separate windows. Alternately, subcategory entries may be displayed as indented lists beneath their associated category. However, as more entries are displayed, the vertical expansion of the list can exceed the size of the desktop. Thus, not all list entries can be displayed at one time.
The amount of branches in the file tree that can be displayed at a time is limited by the amount of desktop space available. The file tree may expand outward in only one direction, for example, from left to right. In such case, as the tree is expanded to show the windows containing the lower tier entries, the higher level entries are temporarily pushed off the desktop. Alternately, the file tree may be configured to reverse direction when the edge of the desktop is reached. In such case, the windows containing the lower tier entries cover the previously-opened windows containing higher level entries.
Furthermore, as each file tree is expanded in one direction, for example, horizontally, the windows containing the branches may become larger in both horizontal and vertical directions, depending upon the number of file entries therein. Open windows of other file trees are therefore covered.
A hyperbolic tree browser, referred to as inXight, has been developed at Xerox Corporation's Palo Alto Research Center in Palo Alto, Calif. Such browser provides a graphical visualization of the myriad links throughout the World Wide Web. The browser provides a "you are here" orientation that allows users to orient themselves not only according to where they are, but also to where they've been. However, no provision is made for preserving a file structure in a semblance of its original format, nor for conserving the area consumed on a display when displaying such browser.
It would therefore be an advantage to provide a computer graphical user interface that can visibly present large file structures on a desktop. It would be a further advantage if such graphical user interface clearly displayed the file categories of interest to the user while maintaining a display of the overall file structure. It would be yet another advantage if categories of such graphical user interface were easily movable to different locations on the desktop.